Protective device for fluid-pressure brakes



s. s; AIKMAN.

PROTECTIVE DEVICE FOR FLUID PRESSURE BRAKES. APPLICATION FILED IIAR. 8' 1921.

1,400,651 Patented Dec. 20, 192-1.

i i 7/ II/IIIII/I/I/I/ mgr V o R 26 any": BURTON SNKMAN 6 BYW/IM ATTORNEY UNHTED STATES PAT NT ,QFFECE.

BURTON s. AIK AN, or MAILWAUKEELW-ISGONSIN, ASSIGNOB o NATIONAL BRAKE e;

ELECTRIC CQMPANX, 0F MILWAUKEE, WISCONSINVA conrone'mqn e11 WISCONSII I-RoTEcmIy-E DEVICE EOE zepurp-mhssumjlmexne Specificgfion pf Letters Patent.' PatentedDeQ; 29, 1921.

p me 191 new .49 5%? ewef l lwm i m y WWW Be it ,known vthe-t I, S. Ar gmmq,

a citizen of the United fitgptes, "residing et This inventipn relates to hrakes, and mog e penticuler liy to -31 valve device.

h i a p e .Q gxpy nventi n is its Pr a ak y'al e-d w-hwing Q9FE1S for w QmQ QeI Y e f cting ie -re plieet en of the brakeseif the px eeg uge the' systetp fal l ep d emeined deg z ee 1 the cc mpe y eg e wme meme is a d ez-zr swnmet i w o 1a fieisi ie su-re brake eqwnmen S lI g m emp eveme applied thereto F ,2 e yerticelsection 9f a portiqn of the bpztke veLVe device, :with the spring locking latch r moved-s Fig.3 11

similar :view, showing ,the eprihg lpckiq g latch i pos E g- 4 a 1Per-fl is ti ned deteillview of the, c01' ecth1g p0rtio ns ef the istqn rod and the spring lpckig lg letch;

- i 1 a p a lp tt y i xse l en bir i ialc v d i ei hew ne th zper naz leeseposifiion; end Eig...6 a s il r liler vl ew of the brake ,vehge device, .shqwingthe pex ts as thrown to service appheetidn ppsitipn, hen h fl id pres u i h ex st m a l below a predetermined. degree; h

In vFig. 1 theixppreved bmkeyelvedeyiqe 1 ,is hawn epplid to e fstgaight ,eir hrek e q p en .s l r t that jdi lb$9 i m prior Patent No. 1,156,8'Zl de ed QQetphQr 9,1- 1Q Len mpyisirge breke cylin e "end emeinreeeriwhgnaqpreeof flhid pressure s pp y c nne te lby' hipfl A th b rek elv eYice m h d Q 1 93 .i

.th c q ipm -zi e d bl en el-119mm,; e ehowp in the dmwing.

Intenpesedhetwefi thebmke valyedeyipe ateuchfend of thecer e cl the bpeke'cyl inder 2 is, a doehle checkitalve devicecomlarising a casing 5, co teining cheekfvel qje s fiend 7 connected by a stemfi.

The chamber 49 cpntain ing check .velve 6 is connectedby pipe 1O to'the bifeke .velve deviceat one end of the car an'd chamber 11 containing check yelve 7 is connected by pipelQ to the other bmkevelve device, while chambevlS intermediate the chechvelyegis @Rl e etheY- q n -15 1 Ceiled eregpd the ,tem v15 -1s a sprmg 20,

' hevi g one end ,se'eu redilto the ihrake valve peeing e d e her fin a eh-W e e be eeaeeeehk byth? $1 11 1 Me u.pt edlqn o ,fieeb i tegral with t the .-h- .1. -m ehe ise -p ten -Yl ed 2 ettem lee-aeeie in rfiz-nhevin ithemb ir 2 a ,pne s tle conpectegl tp' the'j ngeir l fe'iservoir qr source of fluidpreseure supp1 y3 end subeject pn the ,pp ppsjte side to the pressure of etsn i g' 3 Ihe pil}OI} vstem 25 is connected to e .piv- ,otallyrtn dl l nted letch er m} 26, th e Outer, end of iwh eh i ada d wnee e end of ep in'g 2Q.-

:11. elde :b @mmi a .mowe of pi 22 relative to the 'latch erm 26, the end [of t e eiet n. etem z l ed e a e of the pivetgpip gi' 11d .e s pil ihg 36 tends to .hol l th rle he li i t ne ou enp Assuming that the brake velve at the left e Fi i 'th epe ta in hltali .ml h snea 4 b ie" emme my i e wewmee tiowfiml b e the -flu 2h F eeur aeflmitt -em h m i e e evm -fi t bx'queh Por s:i fih i k va tthl e i h Q 1hQ dWW P i O p p 1 d c hazhhef 1 1. check; wgalyef? i's therefore m mo @9 eet .1 .1 the che k Fre 6 i enein ai e fl "its iopempe ition T e ha the threkercyli denflje egnhecfied t0 the oper at- :jgg .bxfgke ,v'a',1je at {the lefto'f the .dmwin wn rmitfinet e beee tofbe appl i ified 1 =l l l :d pressure from the main JG K Q-Q L-BJSSJlPPIi d t0 p et'en c amb 23 n i t ipe uml q jel i pr ex e d the predetei mined Safe -degree for which the 24l1mfl y efldj etedgthe piston 22mm beheld inthe 'ppsitiqnshewn in Fig. 5, in which the leech elm 26, engegesthe free end f spring 20.

Under the above czopditiees, the brake velveharid le fl may be freely manipulated .en d1hayingzi} dqfinwprdly projecting pin 19. e

in the usual manner without any action of the spring 20.

If the main reservoir pressure should fall;

below the predetermined degree, the piston 22 will shift the latch arm 26 out of engagement with the spring 20. Said spring being under tension in this position, the free end of the spring will engage the pin 19 on the collar 18 and shift the valve stem 15 to service application position, as shown in Fig. 6 of the drawing, so that fluid is supplied through the brake valve device to the brake cylinder 2, to effect an application of the brakes; Y

The operator, however, can still control the brakes and can release same, if desired. by moving the brake valve handle against the resistance of the spring.

He must hold the handle, however, since if the handle is released, it will be again moved to application "position.

When'the pressure in the main reservoir has been increased to the predetermined degree, the piston 22 will move the latch arm 26 to its locking position, audit the operator then moves the brake valve handle to release position, the free end of the spring gill be brought to the position shown in s the free end of the spring 20 moves past the latch arm 26, the arm 26 is pushed outwardly, by the engagement of the end of the spring with a beveledface 28 of the projecting portion 29 of the latch arm, this movement being permitted by the movement of the pivot pin 27 in the slot in piston stem 25.

As the operator must hold the brake valve handle in release position to prevent an application of the brakes, this is a constant reminder that the pressure in the main reservoir is too low.

With a double end equipment, as shown in the drawing, since the non-operating brake valve is in emergency position, in which fluid under pressure is suppliedto the pipe 12, if this brake valve should be operated, through the reduction in main reservoir pressure, no harm would result, as the parts would merely be moved to service application position.

It is sometimes desirable for the conductor to be able to apply the brakes and for this purpose, a valve device may be provided comprlsing a casing 30, containing a double beat valve 31 normally held seated in one direction by a spring 32, so as to establish communication from the main reservoir pipe 4 through pipe 33 to pipe 34 which leads to the piston chamber 23 of the brake valve device at opposite ends of the car. Fluid at main reservoir pressure is thus normally maintained on the piston 22.

If the conductor desires I to apply the brakes, he pulls a cord attached to the rock in; arm 35, causing the double beat valve 31 to be depressed so as to cut off communica tion from the main reservoir pipe 4 to the pipe 34 and vent fluid from the pipe The piston 22 will then-be operated by the spring 24 so as to release the latch 26 and cause the spring 20 to shift the brake valve handle to brake application position.

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a fluid pressure brake, the combination with a source of fluid under pressure and a brake valve device, of means operating upon a predetermined reduction in the pressure of said source of pressure for operating said brake valve device to effect an applica tion of the brakes.

2. In a fluid pressure brake, the combination with a main reservoir, a brake cylinder, and a brake valve device having an application position in which fluid under pressure is supplied from the main reservoir to the brake cylinder, of means operating upon a predetermined reduction in main reservoir pressure for moving the brake valve device to application position.

3. In a fluid pressure brake, the combination with a source of fluid under pressure and a brake valve device for applying and releasing the brakes, of a spring tending to move the brake valve device to a position for' effecting an application of the brakes, and means subject to the ressure in said source of pressure for preventing the spring from acting on the brake valve device when the pressureof the source exceeds a predetermined degree.

4. In a fluid pressure brake, the combination with a source of fluid under pressure and a brake valve device for applying and, releasing the brakes, of a spring adapted to move the brake valve device to brake appli cation position, a locking latch for engaging the spring to prevent the same from acting on the brake valve device, and means operated upon a predetermined reduction in pressure of said source for operating said latch to release the spring.

5. In a fluid pressure. brake, the combination with a brake valve device for applying and releasing the brakes, of a spring tending to shift the brake valve device to brake application position, a latch for normally engaging the spring to prevent same from acting on the brake valve device, a piston subjectto fluid under pressure for actuating said latch, and manually operated means for venting fluid from said piston.

6. In a fluid pressure brake, the combination with a brake valve device for applying and releasing the brakes, of a spring tending to shift the brake valve device to brake application position, a latch for normally engaging the spring to prevent same from act ing on the brake valve device, a piston normally subject to fluid under pressure and operated upon a predetermined reduction in fluid pressure for actuating said latch, and a manually operated valve for venting fluid from said piston for also operating same.

7. In a fluid pressure brake, the combination with a source of fluid under pressure and a brake valve device for applying and releasing the brakes, of a spring tending to shift the brake valve device to brake application position, a latch normally engaging the spring to prevent same from acting on the brake valve device, a piston operated upon a predetermined reduction in pressure of said source of pressure for releasing said latch, and a manually operated valve for venting fluid from said piston.

8. In a fluid pressure brake, the combination with a source of fluid under pressure and a brake valve device for applying and releasing the brakes, of a spring tending to shift the brake valve device to brake apphcation position, a latch normally engaging the spring to prevent same from acting on the brake valve device, a piston operated upon a predetermined reduction in pressure of said source of pressure for releasing said latch, and a manually operated double beat valve having one position for supplying fluid to said piston and another position for venting fluid from said piston.

9. In a fluid pressure brake, the combinationwith a source of fluid under pressure and a brake valve device for applying and releasing the brakes, of a piston subject to the pressure of fluid from said source of pressure, a latch operated by said piston, and a spring normally held under tension by said latch and adapted to shift the brake valve device to a brake application position upon release of the latch.

In testimony whereof I have hereunto set my hand.

BURTON S. AIKMAN. 

